Henry a



(No Model.)

H. A. CHASE. SIGNAL TRANSMITTING MECHANISM.

Patented Dec. 29, 1891.

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Nrrnn STATES HENRY A. CHASE, OF BOSTON, MASSACHUSETTS, ASSIGNOR TOALBERT lVATTE, OF SAME PLACE.

SIGNAL-TRANSMITTING MECHANISM.

SPECIFICATION forming part of Letters Patent No. 465,990, dated December29, 1891.

Application filed July 10, 1891.

To all whom it may concern:

Be it known that I, HENRY A. CHASE, of

Boston, county of Suffolk, State of Massachutest-signal, over a thirdwire to a receivingstation.

My present invention has for one of its objects to provide apparatus, aswill be described, whereby a signal from a transmitting mechanism may besent over the metallic circuit to the receiving-station and thereinrecorded Without actuating the fire-alarm-receiving instrument.

Another feature of my present invention consists in providing means, aswill be described, whereby communication may be esfrom any othermechanism connected in the metallic circuit.

Another feature of my present invention consists in a novel constructionof transmitting mechanism,whereby communication may be established fromoutside the transmitting mechanism and between it and thereceivingstation, and vice versa, as will be described. This lastfeature of my present invention is especially advantageous in case it isdesired to summon extra apparatus in time of fire without sending inanother alarm from the transmitting mechanism.

The particular features of my. invention will be pointed out in theclaims at the end of this specification.

Figure 1 is a perspective view of a fire-alarm boX embodying myinvention, the outer door Serial No. 399,033. (No model.)

of the said box; being shown open; Fig. 2, a section of the box shown inFig. 1 on line 2 2; Fig. 3, a detail to be referred to; Fig. 4, adiagram of circuits to enable my invention to be more clearlyunderstood; Fig. 5, a detail to be referred to; Fig. 6, a detail of aportion of the recording-strip, and Fig. '7 a detail of a modified formof receiving apparatus.

The box A, containing the operating parts of my improved transmittingmechanism, as will be described, maybe made of iron or other suitablematerial. The transmitting mechanism referred to, as shown in diagramview, Fig. 4, consists of two signal-transmitting or break Wheels ordisks a a, mounted upon a shaft a and having co-operating with themcontact pens 0r brushes a a The shaft a as shown in Fig. 4, is connectedby a pen or brush a to one line-wire a of a metallic circuit, and thepens a a are also connected by independent paths, as will be described,to the other line-wire a of the said metallic respectively, to thenegative and positive poles of a battery a located in thereceiving-station. sented, has fastened to it a shaft 1), electricallyseparated from the shaft a by suitable insulation, as at b, and theshaft 1), as shown in Fig. 4, has mounted upon it tWo brake-wheels b 6with Which co-operate contact-pens b b The shaft 1) has co-operatingwith it a pen or brush I), connected to the ground I) by a wire bcontact-arms b b and metallic plug b substantially as in the applicationreferred to. The contact-pen Z2 is connected by branch Wire b to oneline-wire a While the pen b is connected by branch wire I) to the otherline- Wire a.

- The brake-wheels b b are arranged on the shaft 12 so that the teeth ofthe said Wheels will not be simultaneously in contact with theirco-operat-ing pens 1) 6 but willbe successively brought in contacttherewith by the the transmitting mechanism, the teeth of the wheel 19being brought in contact with the pen 19 before the teeth of the wheel19 are brought in contact with its pen 12 The pen or brush a3,co-operating with the circuit, the said line-wires being connected,

operation of the motor mechanism actuating The shaft ta as hereinreprebrake-wheel a, is connected by a wire Z) to a contact-pen b formingone-half of one member of a normally-closed circuit-controller B, theother half of the said memberbein g shown as a like contact-pen I)",connected by wire I) to the line-wire a the co-operating member for thesaid contact-arms being shown as a metallic plug b the wires 1) h andcircuitcontroller 13 forming one path for the signaltransmittingmechanism.

The pen or brush a is connected by wire to one member 0 of anormally-closed circuitcontroller or key C, the other member 0 of whichis connected by wire 0 to one member (3 of thenormally-closedcircuit-controller C, the other member 0 of which is connected by wire 0to a spring-arm c co-operating with a like spring-arm 0 connected bywire 0 to the line-wire a", the spring-arms c c constituting anormally-open circuit-controller and being normally separated, as willbe described, by a plug c of insulating material, the said wires andcircuit-controllers forming a second path for the signal-transmittin gmechanism.

The member 0 of the circuit-controller C is connected by a wire 0 to oneend of a resistance-coil c, having its other end connected by a wire 0to the line-wire a. The line-wire a, as shown in Fig. 4, includes withinit, as shown, an electro-magnet 0, herein represented as operating anordinary sounder, such as commonly employed in telegraphwork. Theelectro-magnet 0 is normally shunted out of circuit by means of acircuit-terminal 0 connected by wire 0" to the line-wire a on one sideof the electro-magnet 0 and a co-operatin g terminal 0 aiso connected tothe line-wire a" on the other side of the said electro-magnet.

The line-wire (6 within the receiving'station has connected to it,preferably, two relays (Z (7. for the best results in multiple with eachother, and the line-wire a", within the receiving-station, includes init, as herein shown, the normally-closed circuitcontroller or key I).The line'wires a a" are connected to a pole-changer (1 which may be ofany usual or well"- known construction, by means of which the polarityof the battery a may be reversed, for a purpose as will be described.The circuit-controller D, as represented in Fig. 4:, consists of twoterminals or members (1 d, the terminal (Z having connected to it oneend of a resistance-coil (Z having its other end connected to theterminal (1*. The terminal cl, when moved to open the main line a,preferably co-operates with the terminals cl d of a shunt-loop d d forthe pole-changer, for a purpose as will be described.

The relay (1 in the receiving-station is provided with an armature (Zforming one terminal of a local circuit including a local battery (1 theother terminal for the said local circuit being a back-stop (Z to whichis connected one wire of an electro-magnet (Z controlling the movementof a register d, of any usual or well-known construction, and upon whichthe fire-alarm signal is received. The relay (1', herein shown inmultiple with the relay (Z, is also provided with an armature (1 formingone terminal of a local circuit including a local battery (Z the otherterminal being formed by a back-stop (Z for the said armature, thebackstop (W, as herein shown, being connected to an electro-magnet (Zcontrolling a register (Z of any usual or wellknown construction, andwhich I prefer to hereinafter designate as a test register. The relay dis constructed and adjusted so as to respond to changes in the currentstrength of the main-linecircuit, whereas the relay (1 is constructedand adjusted so as to be una[fected by the changes in current strength,but to be affected by long interruptions or breaks in the circuit, andfor the sake of distinction I prefer to designate the relay cl as theslow relay, and the relay (1' as the fast relay.

The pole-changer d in the receiving-station has co-operating with it anelectro-mag net (Z located in a local circuit provided with a localbattery (1 the terminals for the said local circuit being shown in Fig.4 as a break-wheel (Z mounted on the shaft (Z of the register d, and acontact brush or pen (1.

The break-wheel a of the transmitting mechanism I prefer to designate asthe firealarm wheel, and the break-wheel a as the test-wheel. These twowheels are represented in Fig. at as independent of each other;but inpractice they may be one wheel having a periphery of sufficient width tomake contact with both the pens (t a The metallic plugs b 11 and theinsulating-plug c in practice are preferably secu red to the door e ofthe box, and in the normal condition of the box the door 6 is closed, sothat the metallic plug Z2 is in engagement with the contact-springs I)b, and the insulating-plug 0 in engagement with and between thecontact-springs c a and the metallic-plug b is in engagement with thecontact arms or brushes 1)" b In the normal condition of the box A thedoor 6 is closed and the circuit for the fire-alarm wheel or signal ctis closed by the plug 12 the circuit of the test-wheel d is opened bythe insulating-plug c and the ground-tap circuit in the box is closed bythe plug 1), but is open at the break-wheels b If. It will thus be seenthat in the normal condition of the boxthat is, when the door 6 isclosed-the circuit from the contact-pen a is closed, while the circuitfrom the contact-pen a is open, and consequentlyifthe transmittingmechanism should be operated while the door e is closed the wheel awould transmit a signal, while the wheel a would be rendered practicallyinoperative.

The circuit for the fire-alarm signal may be traced as follows, viz:from the positive pole of the battery through the pole-changer d by wirea. to the wire b ,.then0e by 00R- IIO tact-arm b plug 11 arm I), wire 11to pen a thence by break-wheel a, shaft a brush a wire a, wire c",switch 0", terminal 0 to line-wire a thence through the relays d d,

key D,through the pole-changer (Z to the negative pole of the battery.

The box A, as represented in Figs. 1 and 2, is provided with anauxiliary door 6', having a glass pane e against which bears a lever 6controlling the movement of an escapement for a bell-operating motormechanism, substantially as shown and described in the applicationreferred to.

The signal-transmitting or break wheel shaft a is rotated by a motormechanism not shown, but which may be actuated by hooks e e on apull-bar, substantially as shown and described in the applicationreferred to. Vhen the door 6 is closed, the box is in its normal workingcondition, and an alarm of. fire may be sent to the receiving-station bybreaking the glass 6 and pulling the hook e to start the motormechanism, and

when thus started, the main-line circuit willbe opened by the successivelong breaks in the wheel a, and both relays d (1 will be operated andthe signal received upon the registers 01 (Z I In ord er that an officeror fireman may transmit the signal from the transmitting mechanismwithout sending in an alarm of fire and at the same time operate thesame transmitting mechanism used to send in the fire-alarm signal, thefast relay d, in multiple with the slow relay d, is preferably employed,and preferably a weight or pendulum f, normally in engagement with theescapement-pawl f ,of the motor mechanism is disengaged from the saidmechanism, to allow the motor mechanism to be revolved at asubstantially rapid rate.

Referring now to Fig. 3, I have shown the weight or pendulum f assecured to or formin g part of a clutch (shown as a sleeve or hub fprovided with engaging pins f adapted to look with like pins f on theescapement or pawl f, controlling the movement of the motor mechanism.The clutch-hub f may be disengaged from the escapementpawl by adisengaging mechanism or device (herein shown as a lever f pivoted tothe clutch-hub and acted upon by a spring f having one end fastened tothe lever f and its other end to a stationary part of the motormechanism or to the box A. The clutch-hub f is brought into engagementwith the escapement-pawl when the door e is closed by an engaging device(herein shown as a rod f secured to the lever f and which in practice isextended through a suitable opening in the door and adapted to be struckby a projection or knob f on the side of the door when the latter isclosed. The knob f is provided, as shown in Fig. 1, with a latch f toengage a ring or enlarged head f of the rod f \Vhen the door e isclosed, the knob f strikes the enlarged head f and pushes the lever fand the clutch-hub f inward, so as to engage the clutch with theescapement-pawl. It will readilybe seen that when the clutch-hub isengaged with the pawl the weight or pendulum f controls or regulates therate of movement of the motor mech anism, so that if a signal should besent with the door e closed, as when an alarm of fire is given, themotor mechanism would revolve substantially slowly, and a comparativelylong lapse of time would expire in transmitting this signal, which inpractice would preferably be thirty seconds, whereas when the door 6 isopen and the clutch disengaged from the escapement-pawl it will readilybe seen that if the motor mechanism is set in operation it will revolveat a substantially rapid rate and the signal would be transmitted in asubstantially short time, which may be supposed to be about threeseconds. Then the door 6 is open, the metallic plug U is withdrawn fromthe pens Z) I)" and the circuit governed by the pen a is open, whereasthe insulating-plug 0 is with drawn from between the spring-arms c 0permitting the said arms to come together and close the circuitcontrolled by the pen a, and it is this circuit that is actuated whenthe motor mechanism is operated with-the door open.

The circuit for the transmitting mechanism when the door 6 is open maybe traced .as follows, viz: from the positive pole of the battery athrough the pole-changer d by wire a to wire 0, thence bycontact-terminals 0 0 wire 0, circuit-controller C, wire 0circuit-controller 0, wire 0 to pen a thence by break-wheel a, shaft a,brush a wire a, through wire 0", switch 0 terminals 0 back to wire 0through therelays cl d, circuitcontroller D, pole-changer d to thenegative pole of the battery a The break-wheel a has the same number ofbreaks on its periphery to correspond to the break-wheel a, or it may,if desired, have a different or distinguishing number.

The signal sent by the operation of the m0- tor mechanism with thebox-door 6 open I prefer to designate as the testsignal. The test-signalreferred to, as shown in Fig. 4, is received upon the test-register c1controlled by the test-relay d, which is a fast-operating relay, andowing to the sluggish operation of the relay d the test-signal is notreceived upon the fire-alarm register (Z and when the door is open andthe test-signal sent the register (Z and relay d remain quiet and do notrespond to the short breaks in the main circuit caused by thetransmission of the test-signal. 7

When the motor mechanism is operated to transmit the test-signal, thebreak-wheel a, used to transmit the fire-alarm signal, is rotated andthe contact-surfaces of the said wheel and its co-operating pen a arekept bright and in good condition. Furthermore, the remaining parts ofthe transmitting mechanism. which are actuated when the fire alarmsignal is sent are also operated when the test-signal is sent, and aretherefore kept in good electrical and mechanical condition.

The break-wheels b b provided with the same numberof teeth or breaks,areemployed to transmit the fire-alarm signal from the right or left of theline in case of a break in the metallic circuit, substantially asdescribed in the application referred to, the ground-tap at thetransmitting-instrument being normally closed by the plug 7) when thedoor 0 is closed and normally open at the break-wheels Z1 0 until thelatter are started in rotation, the right and left of the line beingconnected to the ground-tap g at the receiving-instrument by switches gwhich in practice may be controlled by a single lever, as described inthe application referred to.

Thebox A contains within it a polarized bell g having its magnetsincluded in the line-circuit, and by means of which an officer making atest may know from what box the last alarm of fire was sent in. Thisfeature is accomplished, as represented in Fig. 4;, by placing upon theshaft (Z of the testregister a toothed wheel (Z having on its' peripherya number of teeth corresponding to the number of the box or transmittingapparatus from which the last signal was sent to the receiving-station.It will be seen that as soon as the test-register is operated by theofficer sending in his test-signal the local circuit for theelectro-magnet (Z is closed by contact of the teeth of the wheel (Z withthe pen (P and the said magnet operates the pole-changer so as toreverse the current of the main battery a at each closure of the localcircuit controlled by the wheel (Z and the main-line battery being thusreversed the bell g' in the box will be struck, and the oflicer willthus have given to him the number of the box, indicated by thebreak-wheel placed upon the test-register shaft by the proper officer orlire man at the receiving-station, without breaking the metalliccircuit.

If a fireman at the box desires to com municate with the fireman orother officer at the reeeiving-station,he operates thecircuit-controller or key 0 so as to interpose the resistance andthereby weaken the main-line battery sufficient to actuate the relay soas to operate the test-register, upon which may be received the Morsealphabet or any other desired code of signals.

If the fireman or other person at the receiving-station desires toanswer back to the fireman at the box or transmitting mechanism, the keyD is manipulated and the resistance (1 is interposed, which operates thesounder in the box, the fireman at the box at such time separating theterminals 0 c In many instances in times of fire it is desired that thechief or other officer in charge at the tire should be able tocommunicate with the central olfice or receiving-station and atthe sametime have a record of the message sent, so as to settle any dispute asto what message was transmitted. For instance, he may desire to obtainspecial pieces of apparatus without desiring to send in a second alarm.This feature may be accomplished with the apparatus shown in Figs. 5 and7, wherein two circuit-terminals h h on an insulating-plug h areconnected byconductors h to an electro-magnet 7L2 and to acircuitcontrolling key 71., having in shunt with it a resistance It".The electro-magnet 71, is provided with an armature hflforming oneterminal of a local circuit containing a registermagnet h and abell-magnet h, the magnet 7L controlling the register h of any usual orwell-known construction. The register 7L3 and its magnet 7b, thebell-magnet 7L7, resistance h", key 7?, and electro-magnet 7L2 may besocured within a suitable case or box h", which may be carried upon orbe detachably sccured to the wagon of the chief or other officer, andthe circuit-terminals h h may be connected to the parts of the apparatusjust described by a flexible cord h containing the two conductors h hThe terminals h h are designed to be inserted through suitable openingsin the case of the box A and make contact with the arms or springs h h,connected by wires 71?" h to the line-wires a a". At the same time theinsulating-plug 7L separating the contact-terminals h it, strikes themember a of the circuit-controller of the testcircuit and opens thetest-circuit. When the contact-arms h h are connected to thecontact-springs 7t h, the main-line circuit may be operated bymanipulating the key 7r so as to interpose the resistance It" and thusoperate the fast relay (Z and consequently actuate the test-register.

The circuit for the electro-magnet 71, may be traced as follows, viz:from the positive pole of the battery a by wire a to the wire 7L20,thence to the contact plates or arms h 71, wire h magnet 7L2,circuit-controlling key h, wire it, contact-terminals h h, wire 71 towire a", thence through the relays (Z d, circuit-controller I) to thenegative pole of the battery. \Vhen the key 71 is operated by the chiefor other oflicer, a record of the message transmitted is obtained by thechief upon his register h and also the same message is obtained by thereceiving-off1cer upon the testregister (Z If now the officer at thereceiving-station should desire to communicate with the chief at thetransmitting apparatus orbox, he would operate the key D and interposethe resistance (i and thus operate the register h through the magnet W.In this manner danger of the otficer at the receiving-station obtaininga false signal or of sending out apparatus which is not needed isentirely obviated, for by means of the recording-register 71 the chiefor other otticer knows exactly what message was received at thereceiving station.

In order that the number of the box fromwhich the fire-alarm was lastsent may be IIO transmitted to all the boxes in the metallic circuit,the local circuit for the test-register may be closed manually by a key7t. (Shown in Fig. 4:.) The fireman or other olficer in this case firstplaces upon the test-register shaft the wheel (Z bearing the same numberas the number of the box from which the alarm of fire was last sent in,and he would then close the local circuit of the battery (Z by means ofthe key It and start the test-register (Z and thus produce reversals ofthe main-line battery a and actuate all the polar bells in themetalliccircuit.

I prefer to employ two relays d d in multiple with-each other; but I donot desire to limit my invention in this respect, as but a single relay(l, capable of'responding quickly to changes of condition in themetallic circuit, may be employed in connection with a transmittingmechanism capable of operating at varying speeds.

When a single relay, as fl, is employed in the receiving-station, itresponds to both the fire-signal and the test-signal and actuates aregister which may be supposed to be the register (1 (Shown in Fig. 4.)The register (Z may have mounted on its shaft a gear (Z adapted to beengaged by a pinion d", pivotally mounted on the armature d of theregister-magnet d and having secured to or forming part of it a cam orprojection (Z adapted to be brought into engagement with one terminalbrush or pen (Z of a normally-' open local circuit having itscooperating terminal c1 connected, as herein shown, to the magnet of atap-bell 01 by means of which the box number or signal transmitted maybe made known. The pinion (Z is brought into mesh with the gear d by theattraction of the armature (Z andas soon as the register is started inoperation by the closing of its local circuit by the armature d of therelay d the pinion'is revolved and the cam d 'is moved toward theterminal (Z When a firesignal is transmitted, the local circuit of theregister-magnet remains closed for a comparatively long time at eachinterruption of the metallic circuit, and the pinion (Z is revolvedsufficiently far to bring the cam (Z into engagement with thecircuit-terminal c1 and thereby close the local circuit of the bell orother device located therein and by which the operator or firemanat thereceiving-station is notified that an alarm of fire is being received,and the number of the box maybe ascertained from the bell. hen thetest-signal is sent from any box, the speed of the transmittingmechanism is so rapid that the local circuit of the register-magnet doesnot remain closed sufficiently long to permit the cam or projection (Zto be brought into engagement with the terminal (Z and consequently thelocal circuit containing the bell or'other signal is notclosed and nonotice need be taken by the operator of this signal.

The length of the breaks and closures in the test-wheel a are, for thebest results, the same as in the fire-signal wheel a.

I do not herein claim, broadly, a signaling system in which twodifferent and distinct purposes are indicated by the same signalWithoutadditions thereto, subtractions therefrom, or repetitionsthereof, as the same forms the subject-matter of another application,Serial No. 411,028, filed by me November 6, 1891.

I claim 1. In a system for transmitting signals,the combination of thefollowing instrumentalities, viz: a normally-closed electric circuit, asignaltransmitting mechanism included therein and consisting ofbreak-wheels a a and cooperating pens or brushes a a normally in contactwith said break-wheels, independent paths for the current from the pensa a to one side of the line or electric circuit, a normally-closedcircuit-controller in the path of the pen a a normally-opencircuit-controller in the path of the pen a and a resistance 0 connectedto one side of the electric circuit and to the path of the pen a to forma shunt around the break-wheel a, and two relays in the said circuit,both of which are responsive to the signals transmitted over thenormally-closed path of the pen a and one of which is responsive only tothe signals transmitted over the normally-open path of the pen a,substantially as described.

2. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: a metallic circuit, asignal-transmitting mechanism included therein and connected thereto byindependent paths, a normally-closed circuit-controller in one of thesaid paths, a normally-open circuit-controller in the other of saidpaths, a motor mechanism to operate the signal-transmitting mechanism,means for positively changing the speed of the motor mechanism andthereby the speed of the signal-transmitting mechanism, and independentreceiving-instruments included in the metallic circuit, one of the saidinstruments being responsive to the transmitting mechanism Whenoperatedat one speed and not at the other speed, substantially as described. I

3. In a system for transmitting signals, the combination of. thefollowing instrumentalities, viz: a metallic circuit, asignal-transmitting mechanism included in said metallic circuit, a motormechanism to operate it, means for positively changing the rate ofmovement of the motor mechanism and thereby of the speed of thetransmitting mechanism, and two relays included in the metalliccircuitin multiple with each other, substantially as described.

at. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: a metallic circuit, a signal-transmitting mechanism included in said metallic circuit, a motor mechanism tooperate it, means for positively changing the rate of movement of themotor mechanism and thereby of the speed of the transmitting mechanism,two relays included in the metallic circuit in multiple with each other,a pole-changer in the metallic circuit, an electro-magnet to operate it,a register controlled by the operation of one of the said relays, andcircuit-terminals for the pole-changer and an electro-magnet renderedeiiective by the operation of the said register, substantially asdescribed.

5. In a system fortransmitting signals, the combination of the followinginstrumentalities, viz: a metallic circuit, asignal-transmittingmechanism included in said metallic circuit, a motor mechanism tooperate it, means for positively changing the rate of movement of themotor mechanism and thereby of the speed of the transmittingmechanism,two relays included in the metallic circuit in multiple with each other,a pole-changer in the metallic circuit, an electro-maguet to operate it,a shaft, an electro-n'iagnet to control its operation, acircuit-terminal on said shaft connected to the pole-changerelectro-magnet, a second circuit-te1uninal for the pole-changer magnet,a circuit-controller governing the operation of the electro-magnetcontrolling the circuit terminal-carrying shaft, and a polarizedelectro-magnet in the metallic circuit at the transmitting mechanism,substantially as described.

6. In asystem for transmitting signals, the combination of the followinginstrumentalities, Viz: a metallic circuit, a signal-transmittingmechanism included therein and consisting of signal-wheels a a, twoindependent contact pens or terminals connected to the metallic circuitby independent paths and normally in contact with the said signalwheels,circuit-controllers in said paths, a resistance interposed in one of thesaid paths when the circuit-controller is operated,receiving-instruments in the metallic circuit in multiple with eachother, one of the said instruments being operated when the resistance isinterposed in the metallic circuit, and two local circuits disconnectedfrom each other and controlled by the said receivinginstruments,substantially as described.

7. In a fire-alarm system, the combination of the followinginstrumentalities, viz: a metallic circuit, a signal-transmittingmechanism included therein, circuit-terminalsh it, connected to themetallic circuit, an electromagnet 711 ,31 key 72, and a resistance 71;in shunt with said key, adapted to be connected to the circuit-terminalsh h, and relays d d in multiple with each other, one relay, as (1, beingresponsive to the operation of the key 7L3, substantially as described.

8. In a fire-alarm system, the combination of the followinginstrumentalities, viz: a metallic circuit, a signal-trailsmittingmechanism included therein, circuit-terminals h 72. connected to themetallic circuit, an electro' magnet 7L2, a key h and a resistance h inshunt with said key, adapted to be connected to the circuit-terminals hh, a register con trolled in its operation by the electro-magnet 72relays (Z (Z in multiple with each other,

one relay, as d, being responsive to the operation of the key 7r, acircuit-controller D in metallic circuit, and a resistance in shunt withthe circuitcontroller l'), substantially as described.

9. In a fire-alarm system, the combination of the followinginstrumentalities, viz: a metallic circuit, a signal-transmittingmechanism included therein, a normally-closed circuit-controller G incircuit with the signaltransmitting mechanism, circuit-termi nals h h inmultiple with the signal-transmitting mechanism, a portable detachablesignal receiving and transmitting apparatus adapted to be connected incircuit with the circuitterminals h h, relays (Z (1', included in themetallic circuit in multiple with each other, a circuit-controller D,and a resistance in shunt with the circuit-controller D, the circuit ofthe signal-transmitting mechanism being opened when the portableapparatus is coupled in ci rcuit, substantially as described.

10. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: an electric circuit, a signal-boxlocated in said circuit and provided with a door, a signal-transmittingmechanism in said box, included'in said electric circuit, a motormechanism to operate said signaltransmitting mechanism, means forpositivelychanging the rate of movement of the motor mechanism, normallyinactive when the box-door is closed, but adapted to be rendered activewhen the door is open, to change the speed of the motor mechanism andthereby of the transmitting mechanism, and a relay in the said electriccircuit responsive to the varying speeds of the transmitting mechanism,substantially as described.

11. In a firealarm system, the combination of the followingiustrumentalities, Viz: an electric circuit, a fire-alarm box located insaid circuit and provided with a signal-transmitting mechanism havingtwo independent paths for the signal, a motor mechanism for said signal,a positively-acting mechanical speed-controlling device for changing thespeed of the motor mechanism, and a door for the box, providedwithdevices to control the independent paths and the speed-controllingdevice, substantially as described.

12. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: an electric circuit, asignal-transmitting mechanism included in said electric circuit, a motormechanism to operate it,a positively-aeting mechanical speed-changingdevice for changing the rate of movement of the motor mechanism andthereby of the speed of the transmitting mechanism, and a relay in thesaid circuit responsive to the varying speeds of the transmittingmechanism, substantially as described.

13. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: an electric circuit, asignal-transmitting mechanism included in said electric ITS circuit, amotor mechanism to operate it, means for positively changing the rate ofmovement of the motor mechanism and thereby of the speed of thetransmitting mechanism, a relay in the electric circuit, responsive tothe varying speeds of the transmitting mechanism,and a signal mechanismoperated by the relay when the said relay is actuated by one speed oftransmitting mechanism and not by the other speed of the saidtransmitting mechanism, substantially as described.

1t. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: an electric circuit, asignal-transmitting mechanism included in said electric circuit, a motormechanism to operate it, means for positively changing the rate ofmovement of the motor mechanism and thereby .of the speed of thetransmitting mechanism,a relayin the metallic circuit, responsive to theVarying speeds of the transmitting mechanism, and an audible signal uponwhich is sounded the signal when transmitted at one speed and not at theother, substantially as described.

15. In a system for transmitting signals, the combination of thefollowing instrumentalities, viz: a metallic circuit, a signal-transmtting mechanism included in said metallic circuit, a motor mechanism tooperate 1t, a positively-operating mechanical speed-changing device forchanging the rate of movement of the motor mechanism and thereby of thespeed of the transmitting mechanism,a relay in the metallic circuit,responsive to the varying speeds of the transmitting mechanism, apolarized bell in the metallic circuit at the transmitting mechanism, apole-changer 111 the metallic circuit, a shaft controlled in itsoperation by the said relay, and a detachable s1g nal-wheel on saidshaft to operate the polechanger, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HENRY A. CHASE.

Witnesses:

J AS. I1. CHURCHILL, SADIE C. FEARING.

Correction in Letters Patent No. 465,990.

It is hereby certified that the name of the assignee in Letters PatentNo. 465,990, granted December 29, 1891, upon the application of Henry A.Chase, of Boston, Massachusetts, for an improvement inSignal-Transmitting Mechanism, was erroneously written and printedAlbert \Vatte, whereas said name should have been written and printedAlbert Watts and that the said Letters Patent should be read with thiscorrection therein that the same may conform to the record of the casein the Patent Office.

Signed, countersigned, and sealed this 5th day of January, A. 13.1892.

[SEALL] CYRUS BUSSEY,

Assistant Secretary of the Interior. Oountersigned:

W. E. SIMONDS,

Commissioner of Patents.

